typedef struct {
  float dState;
  float iState;
  float iMAX;
  float iMin;
  float pid_K;
  float pid_P;
  float pid_I;
  float pid_D;
  float pid_Freq;
} PID_t;

/**
 * @brief 进行一次PID运算
 *
 * @param pid 结构体
 * @param feedback 反馈值
 * @param setpoint 目标值
 * @return float
 */
float PID_Update(PID_t *pid, float feedback, float setpoint);
